Volume 16 Issue 7, July 2023

Extreme rainfall events are often linked to climate change based on simple thermodynamic arguments, but complex dynamic processes also play a role. Scientists have a responsibility to ensure they provide accurate information to the media and public.

More than just a gemstone, Jon Pownall and Kathryn Cutts explore the history and future directions of garnet as a recorder of pressure, temperature, and time.

Icequake observations were combined with an analytical friction model to measure friction and slip at the bed of an Antarctic ice stream. Friction and slip are found to be highly variable in space and time, controlled by higher-than-expected normal stresses at the ice–bed interface.

Rock organic carbon from glacial runoff, once assumed to be non-bioavailable, is identified as a substrate used by marine sedimentary microbes. This challenges the traditional view that rock organic carbon bypasses the active carbon cycle and indicates an additional source of fossil greenhouse-gas emissions on geological, or possibly even shorter, timescales.

The impact of dissolved oxygen fluctuations on marine ecosystems requires consideration of appropriate temporal and spatial scales.

Analysis of changes in the Earth’s rotation in the Precambrian suggests that day length stabilized at 19 h for 1 billion years due to tidal resonance, which may have been linked to a relatively quiescent period of tectonic activity and biological evolution.

Both magnetic reconnection and kinetic instabilities are required to produce magnetotail plasma eruptions, according to high-resolution global simulations of Earth’s magnetosphere.

Uncertainty in stratospheric water vapour projections is reduced using an observational constraint based on historical co-variations between atmospheric temperature and water vapour.

Atmospheric observations show the presence of shallow mesoscale circulations in the North Atlantic trades and demonstrate their widespread influence on atmospheric moisture and, consequently, clouds.

The low-latitude western boundary current in the South Pacific Ocean strengthened as climate warmed over the past 100 years, according to a coral nitrogen isotope record from the Solomon Sea.

Groundwater springs formed during the retreat of a melting glacier are likely hotspots of methane emissions in the high Arctic according to measurements of methane concentrations in springs recently formed in central Svalbard.

Surface fractures that intersect glacial streams can propagate deeply in ice sheets and can increase their dynamic instability as melting intensifies, according to a new observationally-constrained modelling study of the Greenland Ice Sheet.

Passive seismic observations from the Rutford Ice Stream in Antarctica reveal a highly complex bed and substantial variability in friction and slip rates at the ice–bed interface.

Atmospheric sulfate aerosols—which could cool the atmosphere—were formed in less acidic cloud water in continental interiors in pre-industrial time than today, according to a triple oxygen isotope analysis of sulfate in weathering carbonates.

Ancient, rock-derived organic matter is consumed by micro-organisms in Arctic fjord sediments despite its presumed limited bioavailability, representing a potential source of greenhouse gas emissions, according to compound-specific radiocarbon analyses of lipids from living bacteria.

Overturning circulation that mixes surface and deep water was invariant over the Holocene, suggesting a limited role in rising CO₂ during this time, according to deep-sea coral radiocarbon records.

Mantle lithosphere underlying the stable continental crust of cratons is dense and has experienced cyclic deformation since the Neoproterozoic, leading to the longevity of cratons, according to geological data and geodynamic modelling.

Post-subduction downwelling of lithosphere—or drips—can lead to extension and crustal thinning, influencing the tectonic evolution of continental crust after subduction termination, according to thermo-mechanical simulations.